Over 1. Funds administered by the Salinity Council. Rural Towns Program launches a comprehensive assessment of 6 towns and an investigation of a further 29 towns to assess risks, options and economics of actions. National Conference on Dryland Salinity held in Bendigo, 7 years after the first.
NDSP reviews operation and looks to revise its structure after mid-term review. Dr Richard George awarded the second National W. Wood award for excellence in research in salinity within Australia. Conference on the Future of Wheatbelt Valleys held in Merredin, Seasonal drought breaks with 40—50mm opening season rains. Rural Towns Program releases the economic impact study on six towns. Major infrastructure cost caused by salinity is damage to roads within the towns.
Recharge control limited to better water management within the town mains leakages, more efficient and economical watering of parks and gardens and tree planting within the town. Engineering options are available [ ].
General John Sanderson. Detailed records for surveillance bores showed that in the period —12, groundwater levels continued to rise in and adjacent to areas of salinity hazard in lower landscape positions over much of the region. Western Australian Auditor General releases Report 8 — Management of Salinity — and found 'There is no regular, on-going monitoring and reporting of dryland salinity.
As a result, no one accurately knows the extent, impact, cost and potential spread of dryland salinity'. And as a result of poor coordination, 'efforts to manage dryland salinity are unlikely to achieve any landscape wide improvement. Studies No. Roy Soc. WA Government Printer, Perth. WA 10 7 : Civil Engineers , p WA WA 10 7 : , p WA 6: Engineers J. WA 5 Masters Thesis University of WA. Department of Industrial Development Western Australia 54, p WA 17 4th Series : Department of Industrial Development Western Australia.
WA 21 4th Series : Technical Bulletin Soil Res. Water Manage; 39, A history of salinity in Western Australia — A salty bunch of dates.
Page last updated: Wednesday, 31 March - am. Please note: This content may be out of date and is currently under review. Contact information Richard George. Email Richard George.
Email Ed Barrett-Lennard. See Also Dryland salinity in Western Australia. Managing dryland salinity in south-west Western Australia. Share Tweet Share. Short URL. British settlement Fremantle and Perth. Ensign Dale discovers salt affected country [5]. Bunbury remarks on brackish pools in Avon and Williams Rivers [7]. Very dry season [10]. Dry conditions [14]. Exceptional flood in which salt lakes overflow into the Avon [18]. First artesian borehole sunk in Perth [22]. Poor drainage blamed for deaths in Perth.
Public concern grows [24]. Railway Fremantle to Guildford opened for traffic [25]. Railway extended to Chidlows Well [27]. G Shenton, Mayor of Perth, proposes artesian bores [28]. First gold discoveries at Yeeda Station, Kimberleys [29].
Railway extended to York [31]. Railway extended to Beverley [33]. Gold discovered on the Yilgarn Field [35]. City of Perth Waterworks Company formed [36]. Great Southern Railway built to Albany by a private company [37]. Commission on Agriculture, WA colony [39]. Victoria Reservoir opened [42].
Serious goldrush of the Yilgarn begins [43]. Paddy discovers Hannan gold at Kalgoorlie [44]. Railway from Midland Junction to Walkaway opened [45]. Sir John Forest decides to build a water pipeline to Goldfields [46]. Typhoid, cases, 70 deaths [47]. Salinity in the soils, groundwater, and rivers is a serious threat to ecosystems and human communities in Australia. How farmers might be motivated to creatively tackle this enormous management challenge, and avoid more tipping points in dryland salinity across the continent remains to be seen.
History of Salinometry. Salty News. Thank you! Visit Today : Visit Yesterday : This Month : Total Visit : Hits Today : Total Hits : Who's Online : 1. Under semi-arid conditions, the rainfall has not been sufficient to leach all the salts accumulated below the root zones of native vegetation to the deep groundwater. The clay layers in deep subsoils have hindered the movement of water and salt. This is different from the situation at the foot of slopes and in valley floors of the landscape, where shallow water tables exist and groundwater processes cause soil salinity.
Recent geophysical studies using modern techniques such as airborne electro-magnetics Lawrie, have confirmed the occurrence of salt bulges in deeper soil layers in many landscapes in Australia. Dense sodic subsoils prevent water transmission and restrict leaching; a process that has led to salt accumulation in subsoils root zone layers in amounts detrimental to plant growth.
Significantly, groundwater processes do not influence this form of salinity. Figure 2 schematically explains the soil processes leading to transient salinity in root zone layers of sodic soils. Soil processes and accumulation of salt in root zone layers of sodic soils after Rengasamy, and reproduced by kind permission of CSIRO Publishing.
In Australia, a country whose agricultural area is about 7. Figure 3 illustrates the different forms of dry-land salinity found in the Australian landscape. The problem of transient salinity is not, however, confined to Australia. About 5. Perhaps the large areas once thought to be at risk from rising water tables have to be reconsidered as a result of climate change-induced changes in groundwater levels. Irrigation in Australia has been developed over a wide range of climatic zones including the Mediterranean, tropical and subtropical climates and uses The major irrigation developments have occurred on the Murray River and its tributaries.
The quality of water from river sources used for irrigation is usually good with a very low salt content EC 0. However, discharge of effluents and drainage waters into the river has increased the salinity of the river water in South Australian sections, particularly during summer and low flow situations. Most of the irrigated soils are sodic, with low hydraulic conductivity increasing the probability of salt build-up over time.
Lack of drainage schemes to avert a shallow water table has led to salinity under irrigation. The efforts to pump the saline groundwater to reduce water-table levels and the reuse of it for irrigation have resulted in salinization of the soil layers and, where leaching is sufficient, the soils are becoming sodic.
Recent trends in using industrial effluents with high pH and salinity and recycled water for irrigation Radcliffe, also promotes soil salinization and sodification. The long-term future of irrigated agriculture in Australia depends on maintaining the salt balance through drainage and irrigation methods, soil management, and the choice of suitable plant species and varieties.
In dry-land cropping, fresh water stored in the subsoil is critical for crop production. This amount of salinity can cause an increasing osmotic effect as the soil layer dries due to evapotranspiration. Low osmotic potentials resulting from soil salinity can restrain water uptake by plants and reduces their ability to survive and produce.
Under dry-land conditions, concomitant changes in matric and osmotic potentials determine plant water uptake Rengasamy, The influence of soil texture and type of clay on plant-available water compounds the effect of matric and osmotic potentials. Figure 4 data from Rengasamy et al. Whereas, when the soil salinity measured in the laboratory as EC soil:water extract is 0.
In areas affected by transient salinity where the water table is deep around 15 m , species with high evapotranspiration can concentrate more salt in the root zone and hinder the production of other plants: in saline areas where the water table is shallow around 2 m , the same species may help in deepening the groundwater levels.
However, the increasing accumulation of salts will decrease plant leaf area indices and their transpiration rates. Thus, soil processes specific to each type of salinity dictate the strategies for plant-based solutions to different forms of salinity.
Although sodicity is a major problem in Australia, a number of soils have multiple problems in different layers of their soil profile Rengasamy, For example, the topsoil can be sodic while the subsoil is saline.
When a saline-tolerant durum wheat variety was grown in this type of sodic soil, the yield was similar to that of a less saline-tolerant variety. On further investigation it was found that topsoil sodicity and alkaline pH 9.
Multiple problems can arise when the salts accumulated contain borates and carbonates in toxic amounts, as found in extensive areas of Australia with alkaline subsoil pH Rengasamy, and also in the Indian subcontinent Gupta and Abrol, and other parts of the world Shainberg and Letey, There is a gap in our knowledge in identifying the predominant, or a common, factor when different issues cause constraints to plant growth in different soil layers.
The uncertainty in our ability to separate the effects of these factors will need to be overcome for developing varieties adapted to the various physico-chemical constraints of soil layers. The lack of success of breeding programmes in developing commercially successful salt-tolerant crops is due to breeders' preference for evaluating their genetic material in idealized conditions. Successful development of boron-resistant wheat varieties in Australia has been achieved through attention to soil-based problems Rathjen et al.
A co-operative effort by a team of scientists from the different disciplines of soil science, hydrology, agronomy, plant physiology, and plant breeding including genetic engineering, is necessary to combat the problem of world salinization. Barret-Lennard G. The interaction between waterlogging and salinity in higher plants: causes, consequences and implications. Plant and Soil , 35 — Distribution of sodic soils: the world scene.
Sodic soils: distribution , properties , management and environmental consequences. New York: Oxford University Press, 19— Cooper DS. Genetics and agronomy of transient salinity in Triticum durum and T. S alinization of land and water resources. Human causes, extent, management and case studies.
Salt-affected soils: their reclamation and management for crop production. Advances in Soil Science 11 , — Preclearing hydrology of the western Australia wheatbelt: target for the future? Plant and Soil , — Origin of dissolved salts in a large, semi-arid groundwater system: Murray Basin, Australia.
Marine and Freshwater Research 52 , 41 — Hillel D. Soil salinity: Historical and contemporary perspectives.
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